Aminoacetonitrile derivatives (AADs) are a class of anthelmintics effective against drug-resistant nematodes. The nematodes, or roundworms, comprise a large number of pathogens of man and domestic animals. Gastrointestinal nematodes, such as Haemonchus contortus, are major parasites of ruminants that cause substantial economic losses to livestock production worldwide.
Monepantel (MPL) (N-[(1S)-1-cyano-2-(5-cyano-2-trifluoromethyl-phenoxy)-1-methyl-ethyl]-4-trifluoromethylsulfanyl-benzamide) is an example of such an AAD and has been approved as a nematocide for the treatment of sheep gastrointestinal parasites.

MPL has been shown to be efficacious against various species of livestock-pathogenic nematodes.
As a nematocide, MPL affects ligand-gated ion channels leading to interference of signal transduction at neuromuscular synapse. The affected parasites will then experience dysregulation in muscle contraction, paralysis, necrosis and moulting defects. Three nicotinic acetylcholine receptor (nAChR) related genes have been identified as the primary targets of MPL and all of the three genes encode for the proteins representing the DEG-3 subfamily of nAChR subunits that are only present in nematodes. The DEG-3 gene encodes a nAChR α-subunit which holds resemblance to that of α7 subunit in second transmembrane domain.
It has now surprisingly been found that AADs are also effective in the treatment of cancers. One of the greatest challenges in medicine during that past 50 years has been the identification of drugs that can effectively kill tumour cells without harming normal tissues. The side-effect profile of almost all known classes of anticancer drug is substantive in limiting the physician's ability to treat the cancer patient, especially at late stages when resistance to the drug often develops. Although other antihelminthic drugs such as benzimidazoles have been known to be effective in controlling the growth and development of cancerous cells, the surprising anti-cancer activity and low toxicity of compounds of formula (I), such as MPL, allows more flexible dosing regimens for cancer therapy with limited side effects.